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Rapamycin extends mouse lifespan 9–14%
NAD+ precursors reverse aging in humans
Blue-light glasses improve sleep quality
Walking 10 min after meals blunts glucose
Verdict change — caffeine half-life downgraded

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Methionine and Glycine balance for humans — Whalespan

Content›Video›Methionine and Glycine balan…

Methionine and Glycine balance for humans

Paul Saladino10m · 2022-03-06

Claims Made

28

Claims Supported

24

Support Rate

86%

Support rate

24 of 28 claims supported

24 supported4 partial / not

Claims from this content

21

✓Well SupportedHeart and Soil's 'Skin Hair and Nails' product, containing trachea and scapular cartilage, liver, and bone marrow, is beneficial for skin, hair, nails, bones, and joints.✓Well SupportedAn excess of methionine without sufficient glycine can be harmful.✓Well SupportedRestricting methionine for longevity is unnecessary; providing sufficient glycine is an alternative approach.✓Well SupportedA diet with increased glycine levels can increase healthy lifespan in mice.✓Well Supported

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A. Volkovreader

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Ground beef is beneficial partly because it contains collagen from chewy, sinewy parts of the animal.

✓Well SupportedHydrolyzed collagen powder provides a more concentrated source of proline, glycine, and hydroxyproline compared to typical food sources like steak.

✓Well SupportedSources of glycine include collagenous meat, chewy meat, chuck roast, stew meat, tendons, and bone broth made from tendons or knuckle bones.

◐Partially SupportedThe alleviating effect of dietary glycine on methionine toxicity is due to the restoration of hepatic glycine levels.

◐Partially SupportedConsuming fat and chewy bits from steak provides collagen-rich pieces that are higher in glycine.

◐Partially SupportedTrachea and scapular cartilage collagen can aid wound healing, tissue regeneration, and growth of skin, hair, and nails.

◐Partially SupportedMethionine restriction profoundly decreases mitochondrial reactive oxygen species production and oxidative damage to mitochondrial DNA in rats.

◐Partially SupportedMethionine restriction may extend life or mitigate oxidative damage, based on animal studies.

◐Partially SupportedBones contain collagen, which is high in glycine.

◐Partially SupportedA carnivore diet should aim for a collagen to meat ratio of at least 10 grams of collagen per 100 grams of muscle meat.

✕Not SupportedLong-term ketosis is detrimental to human health.

◐Partially SupportedOrganic acid tests can be used to check for adequate collagen or glycine levels.

◐Partially SupportedCertain beef cuts contain 6.26% to 8.57% glycine.

◐Partially SupportedSupplementation with glycine is necessary if not consuming membranous or tender tissues.

✕Not SupportedMainstream collagens are often low quality, derived from hooves, but are still better than nothing.

◐Partially SupportedBeef contains more glycine than methionine.

◐Partially SupportedEating connective tissue, fat, and membranes from ribeye steaks provides valuable nutrients.